Properties of Magma

Physical & Chemical Properties An element is a substance that cannot be broken down into other substances (ex. Carbon, Hydrogen, Oxygen). A compound is a substance made of 2 or more elements that have been chemically combined (ex. Water, carbon dioxide, and table salt).

Physical & Chemical Properties Each substance has a particular set of physical & chemical properties. Their properties can be used to identify a substance or to predict how it will behave. A physical property is any characteristic of a substance that can be observed or measured without changing the composition of the substance (ex. Density, hardness, melting & boiling points).

Physical & Chemical Properties A chemical property is any property that produces a change in the composition of matter (ex. The ability to burn, combine or react with other substances). The physical property of liquids called viscosity is the resistance of a liquid to flow. Because liquids differ in viscosity, some liquids flow more easily than others. The greater the viscosity of a liquid, the slower it flows (like honey).

Viscosity of Magma The viscosity of magma depends upon its silica content and temperature. The compound silica (the major component of magma) is made up of particles of the elements oxygen & silicon. The amount of silica in magma helps to determine its viscosity. The less silica magma contains, the lower its viscosity (flows very easily).

Viscosity of Magma Viscosity increases as temperature decreases. Pahoehoe is fast-moving, hot lava that has low viscosity. Lava that is cooler and slower-moving is called aa. Pahoehoe aa